(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

decide if sqrt2 + sqrt5 +sqrt7 is rational or irrational, with proof

2. Relevant equations

3. The attempt at a solution

i assumed that it was rational, the equation =r

sqrt2 + sqrt 5=r- sqrt7

7 + 2sqrt10=r^2 + 7 -2r*sqrt7

2sqrt10=r^2 -2r*sqrt7

could i have a hint on how to rearrange this, i have already proved in an earlier question that sqrt2, sqrt5, sqrt7 are irrational

thankyou

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# Homework Help: Proving irrationality

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